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Tailoring Morphology of PVDF-HFP Membrane via One-step Reactive Vapor Induced Phase Separation for Efficient Oil-Water Separation

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Chinese Journal of Polymer Science 2021年第5期39卷 610-619,I0007页

作者： peng Huo Cheng-Tang Zhong xiao-peng Xiong Department of Materials Science and Engineering College of MaterialsXiamen UniversityXiamen 361005China

Poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)receives increasing attention in membrane separation field based on its advantages such as high mechanical strength,thermal and chemical ***,controlling the microporous structure is still *** this work,we attempted to tailor the morphology of PVDF-HFP membrane via a one-step reactive vapor induced phase separation ***,PVDF-HFP was dissolved in a volatile solvent and then was cast in an ammonia water vapor *** complete evaporation of solvent,membranes with adjustable porous structure were prepared,and the microstructures of the membranes were analyzed by scanning electron microscopy,Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy and X-ray diffraction *** on the results,a mechanism of dehydrofluorination induced cross-linking of PVDF-HFP has been suggested to understand the morphology *** our knowledge,this is the first report of one-step reactive vapor induced phase separation strategy to tailor morphology of PVDF-HFP *** addition,the membranes prepared in the ammonia water vapor exhibited enhanced mechanical strength and achieved satisfactory separation efficiency for water-in-oil emulsions,suggesting promising potential.

关键词： PVDF-HFP Membrane Tailoring Vapor induced phase separation Oil-water separation

Effects of synthetic jet frequency on the separated flow in a diffusing S-duct

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航空动力学报 2016年第2期31卷 432-442页

作者： HE peng DONG jin-zhong School of Energy and Power Engineering Beijing University of Aeronautics and Astronautics

Numerical simulations were carried out to investigate the effects of synthetic jet actuation frequency on the separated flow in a diffusing *** Reynolds number based on the entrance height was9.78×*** first,the numerical model was validated with experimental data,and then,the interaction between the separated flow and the synthetic jets at different frequencies was *** results demonstrate that the control effect is significantly dependent on the momentum mixing enhancement between inside of the separated boundary layer and the outer *** exists a narrow range of actuation frequency,in which effective separation control can be achieved using synthetic jets.A dimensionless frequency F+=1.0is identified as the optimal frequency,with a momentum coefficient of 1.62×10-3,the separation area is reduced about46%,and the aerodynamic performance of the S-duct is also greatly improved compared to uncontrolled *** analysis reveals that the choice of actuation frequency is mainly determined by the momentum flux produced by a single ejection and the spacing between adjacent ejections,the optimal frequency case can be understood as a balance between the two *** addition,it is found that the synthetic jets can also suppress the secondary flows while decreasing the separation.

关键词： active flow control boundary layer separation synthetic jet actuation frequency S-duct

Clinical Study with Randomized Control on the Therapy of Integrated Chinese and Western Medicine in Treating Neurological Autoimmune Diseases:A Meta-Analysis

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World Journal of Traditional Chinese Medicine 2018年第3期4卷 85-95页

作者： xiao-Yan peng jin-Yun Ma xiao-Dong Cheng Institute of Clinical Immunology Yueyang Hospital of Integrated Traditional Chinese and Western Medicine Shanghai University of Traditional Chinese Medicine

Objective: The main objective of this study is to evaluate the effects of integrated Chinese and Western medicine in the treatment of neurological autoimmune diseases. Materials and Methods: The literature was comprehensively searched to collect the randomized controlled trials about integrated Chinese and Western medicine in the treatment of neurological autoimmune diseases. Neurological autoimmune diseases mainly occur in the central nervous system(CNS) and peripheral nervous system. Therefore, multiple sclerosis(MS) was chosen as the representative in the CNS, and Guillain–Barre syndrome(GBS) was chosen as the representative in the peripheral nervous system. Extended Disability Status Scale(EDSS) score, effective rate, clinical symptom score, neurological functional sign score, recurrence frequency, and incidence rate of adverse reactions were chosen as the markers of outcome variables of MS, and the effective rate and Hughes score were also chosen as the markers of outcome variables of GBS. Results: For MS, the results showed that there was a significant difference in statistical analysis between the experimental group and the control group in EDSS score, the effective rate, and the recurrence frequency. However, through the comparison of clinical symptom score, neurological functional sign score, and incidence rate of adverse reaction of both two groups, the results showed that there was no significant difference in the statistical analysis. For GBS, through the comparison of effective rate and Hughes score of both two groups, the results showed that there was a significant difference in statistical analysis. Conclusions: The study demonstrated that compared with Western medicine, the therapy of integrated Chinese and Western medicine was more effective in treating neurological autoimmune diseases.

关键词： Guillain-Barre syndrome integrated Chinese and Western medicine meta-analysis multiple sclerosis randomized controlled trial

Carbon cycle in response to residue management and fertilizer application in a cotton field in arid Northwest China

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Journal of Integrative Agriculture 2019年第5期18卷 1103-1119页

作者： ZHANG peng-peng XU Shou-zhen ZHANG Guo-juan PU xiao-zhen WANG jin ZHANG Wang-feng The Key Laboratory of Oasis Eco-agriculture Xinjiang Production and Construction Corps Agricultural College Shihezi University College of Life Science Shihezi University Wulanwusu Agro-meteorological Experiment Station of Xinjiang

Understanding the influence of farming practices on carbon(C) cycling is important for maintaining soil quality and mitigating climate change, especially in arid regions where soil infertility, water deficiency, and climate change had significantly influenced on agroecosystem. A field experiment was set up in 2009 to examine the influence of residue management and fertilizer application on the C cycle in a cotton field in the Xinjiang Uygur Autonomous Region of Northwest China. The study included two residue management practices(residue incorporation(S) and residue removal(NS)) and four fertilizer treatments(no fertilizer(CK), organic manure(OM), chemical fertilizer(NPK), chemical fertilizer plus organic manure(NPK+OM)). Soil organic carbon(SOC) and some of its labile fractions, soil CO_2 flux, and canopy apparent photosynthesis were measured during the cotton growing seasons in 2015 and 2016. The results showed that SOC, labile SOC fractions, canopy apparent photosynthesis, and soil CO_2 emission were significantly greater in S+NPK+OM(residue incorporation+chemical fertilizer) than in the other treatments. Analysis of all data showed that canopy apparent photosynthesis and soil CO_2 emission increased as SOC increased. The S+OM(residue incorporation+organic manure) and S+NPK+OM treatments were greater for soil C sequestration, whereas the other treatments resulted in soil C loss. The S+NPK treatment is currently the standard management practice in Xinjiang. The results of this study indicate that S+NPK cannot offset soil C losses due to organic matter decomposition and autotrophic respiration. Residue return combined with NPK fertilizer and organic manure application is the preferred strategy in arid regions for increasing soil C sequestration.

关键词： residue fertilizer SOC pool canopy apparent photosynthesis soil respiration soil C balance

Greatly Enhanced Hydrolytic Degradation Ability of Poly(L-lactide) Achieved by Adding Poly(ethylene glycol)

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Chinese Journal of Polymer Science 2017年第3期35卷 386-399页

作者： yang-peng wang xiao wei jin duan jing-hui yang nan zhang ting huang 王勇 School of Materials Science and Engineering Southwest Jiaotong University Key Laboratory of Advanced Technologies of Materials Ministry of Education of China Chengdu 610031 China

Plasticized poly(L-lactide)(PLLA) materials have been applied in many fields and the microstructure performance of such materials attracts much attention of researchers. However, few reports declared the hydrolytic degradation ability of the plasticized PLLA materials. In this article, a small quantity of poly(ethylene glycol)(PEG) was introduced into PLLA, which aimed to understand the hydrolytic degradation behavior of the plasticized PLLA materials. The microstructures of the plasticized samples were comparatively investigated using scanning electron microscopy(SEM), wide angle X-ray diffraction(WAXD), differential scanning calorimetry(DSC) and Flourier transform infrared spectroscopy(FTIR), etc. The results demonstrated that PEG improved the hydrophilicity of sample surface, and the relatively high content of PEG enhanced the crystallization ability of PLLA matrix. The hydrolytic degradation measurement was carried out at 60 ℃ in an alkaline solution of pH = 12. The results demonstrated that the plasticized PLLA samples exhibited accelerated hydrolytic degradation compared with the pure PLLA sample, and the hydrolytic degradation was also dependent on the PEG content. Further results demonstrated that PEG induced the change of hydrolytic degradation mechanism possibly due to the good dissolution ability of PEG in water, which provided more paths for the penetration of water. Furthermore, the microstructure evolution of the plasticized PLLA during the hydrolytic degradation process was also investigated, and the results demonstrated the occurrence of PLLA crystallization, which was possibly contributed to the decreased hydrolytic degradation rate observed at relatively long hydrolytic degradation time. This work is of great significance and may open a new way for promoting the reclamation of PLLA waste material.

关键词： PLLA/PEG Microstructure Hydrolytic degradation

DIRECT ITERATIVE METHODS FOR RANK DEFICIENT GENERALIZED LEAST SQUARES PROBLEMS

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Journal of Computational Mathematics 2000年第4期18卷 439-448页

作者： jin-yun Yuan xiao-qing jin Departamento de Matematica Universidade Federal do ParanaCuritibaBrazil Faculty of Science and Technology University of MacaoMacaoChina

The generalized least squares (LS) problem ... (Ax - b)[sup TW[sup -1](Ax - b) appears in, many application areas. Here W is an m × m symmetric positive definite matrix and A is an m × n matrix with m ≥ n. Since the problem has many solutions in rank deficient case, some special preconditioned techniques are adapted to obtain the minimum 2-norm solution. A block SOR method and the preconditioned conjugate gradient (PCG) method are proposed here. Convergence and optimal relaxation parameter for the block SOR method are studied. An error bound for the PCG method is given. The comparison of these methods is investigated. Some remarks on the implementation of the methods and the operation cost are given as well. [ABSTRACT FROM AUTHOR]

关键词： rank deficient generalized LS problem block SOR method PCG method convergence optimal parameter

Synthesis,and anti-inflammatory activities of gentiopicroside derivatives

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Chinese Journal of Natural Medicines 2022年第4期20卷 309-320页

作者： ZHANG Qi-Li XIA peng-Fei peng Xue-jing WU xiao-Yu jin Hua ZHANG Jian ZHAO Lei Gansu University of Chinese Medicine Lanzhou 730000China Key Laboratory of Chemistry and Quality of TCM of the College of Gansu Province Lanzhou 730000China Gansu Province Engineering Laboratory for TCM Standardization Technology and Popularization Lanzhou 730000China

A series of 26 novel derivatives have been synthesized through structural modification of gentiopicroside,a lead COX-2 *** their in vivo and in vitro anti-inflammatory activities have been *** in vitro anti-inflammatory activities were evaluated against NO,PGE2,and IL-6 production in the mouse macrophage cell line RAW264.7 stimulated by *** showed that most compounds had good inhibitory *** in vivo inhibitory activities were further tested against xylene-induced mouse ear *** demonstrated that several compounds were more active than the parent compound *** inhibition rate of the most active compound P23(57.26%)was higher than positive control drug celecoxib(46.05%)at dose 0.28 *** docking suggested that these compounds might bind to COX-2 and *** of them,e.g P7,P14,P16,P21,P23,and P24,had high docking scores in accordance with their potency of the anti-inflammatory activitiy,that downregulation of the inflammatory factors,NO,PGE2,and IL-6,was possibly associated with the suppression of iNOS and ***,these gentiopicroside derivatives may represent a novel class of COX-2 and iNOS inhibitors.

关键词： Gentiopicroside derivatives Structural modification Anti-inflammatory activity Selective inhibitors

A Bregman-Style Improved ADMM and its Linearized Version in the Nonconvex Setting:Convergence and Rate Analyses

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Journal of the Operations Research Society of China 2024年第2期12卷 298-340页

作者： peng-Jie Liu jin-Bao Jian Hu Shao xiao-Quan Wang Jia-Wei Xu xiao-Yu Wu School of Mathematics Jiangsu Center for Applied MathematicsChina University of Mining and TechnologyXuzhou 221116JiangsuChina School of Mathematics and Physics Center for Applied Mathematics of GuangxiGuangxi Minzu UniversityNanning 530006GuangxiChina Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong KongChina School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105HunanChina

This work explores a family of two-block nonconvex optimization problems subject to linear *** first introduce a simple but universal Bregman-style improved alternating direction method of multipliers(ADMM)based on the iteration framework of ADMM and the Bregman ***,we utilize the smooth performance of one of the components to develop a linearized version of *** to the traditional ADMM,both proposed methods integrate a convex combination strategy into the multiplier update *** each proposed method,we demonstrate the convergence of the entire iteration sequence to a unique critical point of the augmented Lagrangian function utilizing the powerful Kurdyka–Łojasiewicz property,and we also derive convergence rates for both the sequence of merit function values and the iteration ***,some numerical results show that the proposed methods are effective and encouraging for the Lasso model.

关键词： Nonconvex optimization Alternating direction method of multipliers Kurdyka-Lojasiewicz property Convergence rate

Total ionizing dose effect modeling method for CMOS digital-integrated circuit

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Nuclear Science and Techniques 2024年第2期35卷 32-46页

作者： Bo Liang jin-Hui Liu xiao-peng Zhang Gang Liu Wen-Dan Tan Xin-Dan Zhang School of Computer Science and Technology Xidian UniversityXi’an 710071China

Simulating the total ionizing dose(TID)of an electrical system using transistor-level models can be difficult and expensive,particularly for digital-integrated circuits(ICs).In this study,a method for modeling TID effects in complementary metaloxide semiconductor(CMOS)digital ICs based on the input/output buffer information specification(IBIS)was *** digital IC was first divided into three parts based on its internal structure:the input buffer,output buffer,and functional *** of these three parts was separately *** the IBIS model,the transistor V-I characteristic curves of the buffers were processed,and the physical parameters were extracted and modeled using *** the functional area,logic functions were modeled in VHDL according to the data sheet.A golden digital IC model was developed by combining the input buffer,output buffer,and functional area ***,the golden ratio was reconstructed based on TID experimental data,enabling the assessment of TID effects on the threshold voltage,carrier mobility,and time series of the digital *** experiments were conducted using a CMOS non-inverting multiplexer,NC7SZ157,and the results were compared with the simulation results,which showed that the relative errors were less than 2%at each dose *** confirms the practicality and accuracy of the proposed modeling *** TID effect model for digital ICs developed using this modeling technique includes both the logical function of the IC and changes in electrical properties and functional degradation impacted by TID,which has potential applications in the design of radiation-hardening tolerance in digital ICs.

关键词： CMOS digital-integrated circuit Total ionizing dose IBIS model Behavior-physical hybrid model Physical parameters